Doxorubicin encapsulated in stealth liposomes conferred with light-triggered drug release

Lipid-based nanosystems: the next generation of cancer immune therapy

Immunotherapy has become an important part of the oncotherapy arsenal. Its applicability in various cancer types is impressive, as well as its use of endogenous mechanisms to achieve desired ends. However, off-target or on-target-off-tumor toxicity, limited activity, lack of control in combination treatments and, especially for solid tumors, low local accumulation, have collectively limited clinical use thereof. These limitations are partially alleviated by delivery systems. Lipid-based nanoparticles (NPs) have emerged as revolutionary carriers due to favorable physicochemical characteristics, with specific applications and strengths particularly useful in immunotherapeutic agent delivery. The aim of this review is to highlight the challenges faced by immunotherapy and how lipid-based NPs have been, and may be further utilized to address such challenges. We discuss recent fundamental and clinical applications of NPs in a range of areas and provide a detailed discussion of the main obstacles in immune checkpoint inhibition therapies, adoptive cellular therapies, and cytokine therapies. We highlight how lipid-based nanosystems could address these through either delivery, direct modulation of the immune system, or targeting of the immunosuppressive tumor microenvironment. We explore advanced and emerging liposomal and lipid nanoparticle (LNP) systems for nucleic acid delivery, intrinsic and extrinsic stimulus-responsive formulations, and biomimetic lipid-based nanosystems in immunotherapy. Finally, we discuss the key challenges relating to the clinical use of lipid-based NP immunotherapies, suggesting future research directions for the near term to realize the potential of these innovative lipid-based nanosystems, as they become the crucial steppingstone towards the necessary enhancement of the efficacy of immunotherapy.

Calcein release from DPPC liposomes by phospholipase A2 activity: Effect of cholesterol and amphipathic copolymers

In this study, we evaluated the impact of incorporating diblock and triblock amphiphilic copolymers, as well as cholesterol into DPPC liposomes on the release of a model molecule, calcein, mediated by exogenous phospholipase A2 activity. Our findings show that calcein release slows down in the presence of copolymers at low concentration, while at high concentration, the calcein release profile resembles that of the DPPC control. Additionally, calcein release mediated by exogenous PLA2 decreases as the amount of solubilized cholesterol increases, with a maximum between 18 mol% and 20 mol%. At concentrations higher than 24 mol%, no calcein release was observed. Studies conducted on HEK-293 and HeLa cells revealed that DPPC liposomes reduced viability by only 5% and 12%, respectively, after 3 hours of incubation, while DPPC liposome in presence of 33 mol% of Cholesterol reduced viability by approximately 11% and 23%, respectively, during the same incubation period. For formulations containing copolymers at low and high concentrations, cell viability decreased by approximately 20% and 40%, respectively, after 3 hours of incubation. Based on these preliminary results, we can conclude that the presence of amphiphilic copolymers at low concentration can be used in the design of new DPPC liposomes, and together with cholesterol, they can modulate liposome stabilization. The new formulations showed low cytotoxicity in HEK-293 cells, and it was observed that calcein release depended entirely on PLA2 activity and the presence of calcium ions.

Nanocarriers address intracellular barriers for efficient drug delivery, overcoming drug resistance, subcellular targeting and controlled release

The cellular barriers are major bottlenecks for bioactive compounds entering into cells to accomplish their biological functions, which limits their biomedical applications. Nanocarriers have demonstrated high potential and benefits for encapsulating bioactive compounds and efficiently delivering them into target cells by overcoming a cascade of intracellular barriers to achieve desirable therapeutic and diagnostic effects. In this review, we introduce the cellular barriers ahead of drug delivery and nanocarriers, as well as summarize recent advances and strategies of nanocarriers for increasing internalization with cells, promoting intracellular trafficking, overcoming drug resistance, targeting subcellular locations and controlled drug release. Lastly, the future perspectives of nanocarriers for intracellular drug delivery are discussed, which mainly focus on potential challenges and future directions. Our review presents an overview of intracellular drug delivery by nanocarriers, which may encourage the future development of nanocarriers for efficient and precision drug delivery into a wide range of cells and subcellular targets.

Nanomedicine as a multimodal therapeutic paradigm against cancer: on the way forward in advancing precision therapy

Recent years have witnessed dramatic improvements in nanotechnology-based cancer therapeutics, and it continues to evolve from the use of conventional therapies (chemotherapy, surgery, and radiotherapy) to increasingly multi-complex approaches incorporating thermal energy-based tumor ablation (e.g. magnetic hyperthermia and photothermal therapy), dynamic therapy (e.g. photodynamic therapy), gene therapy, sonodynamic therapy (e.g. ultrasound), immunotherapy, and more recently real-time treatment efficacy monitoring (e.g. theranostic MRI-sensitive nanoparticles). Unlike monotherapy, these multimodal therapies (bimodal, i.e., a combination of two therapies, and trimodal, i.e., a combination of more than two therapies) incorporating nanoplatforms have tremendous potential to improve the tumor tissue penetration and retention of therapeutic agents through selective active/passive targeting effects. These combinatorial therapies can correspondingly alleviate drug response against hypoxic/acidic and immunosuppressive tumor microenvironments and promote/induce tumor cell death through various multi-mechanisms such as apoptosis, autophagy, and reactive oxygen-based cytotoxicity, e.g., ferroptosis, etc. These multi-faced approaches such as targeting the tumor vasculature, neoangiogenic vessels, drug-resistant cancer stem cells (CSCs), preventing intra/extravasation to reduce metastatic growth, and modulation of antitumor immune responses work complementary to each other, enhancing treatment efficacy. In this review, we discuss recent advances in different nanotechnology-mediated synergistic/additive combination therapies, emphasizing their underlying mechanisms for improving cancer prognosis and survival outcomes. Additionally, significant challenges such as CSCs, hypoxia, immunosuppression, and distant/local metastasis associated with therapy resistance and tumor recurrences are reviewed. Furthermore, to improve the clinical precision of these multimodal nanoplatforms in cancer treatment, their successful bench-to-clinic translation with controlled and localized drug-release kinetics, maximizing the therapeutic window while addressing safety and regulatory concerns are discussed. As we advance further, exploiting these strategies in clinically more relevant models such as patient-derived xenografts and 3D organoids will pave the way for the application of precision therapy.

Recent Trends in Nanocarrier-Based Drug Delivery System for Prostate Cancer

Prostate cancer remains a significant global health concern, requiring innovative approaches for improved therapeutic outcomes. In recent years, nanoparticle-based drug delivery systems have emerged as promising strategies to address the limitations of conventional cancer chemotherapy. The key trends include utilizing nanoparticles for enhancing drug delivery to prostate cancer cells. Nanoparticles have some advantages such as improved drug solubility, prolonged circulation time, and targeted delivery of drugs. Encapsulation of chemotherapeutic agents within nanoparticles allows for controlled release kinetics, reducing systemic toxicity while maintaining therapeutic efficacy. Additionally, site-specific accumulation within the prostate tumor microenvironment is made possible by the functionalization of nanocarrier with targeted ligands, improving therapeutic effectiveness. This article highlights the basics of prostate cancer, statistics of prostate cancer, mechanism of multidrug resistance, targeting approach, and different types of nanocarrier used for the treatment of prostate cancer. It also includes the applications of nanocarriers for the treatment of prostate cancer and clinical trial studies to validate the safety and efficacy of the innovative drug delivery systems. The article focused on developing nanocarrier-based drug delivery systems, with the goal of translating these advancements into clinical applications in the future.

Versatile Design of Organic Polymeric Nanoparticles for Photodynamic Therapy of Prostate Cancer

Radical prostatectomy is a primary treatment option for localized prostate cancer (PCa), although high rates of recurrence are commonly observed postsurgery. Photodynamic therapy (PDT) has demonstrated efficacy in treating nonmetastatic localized PCa with a low incidence of adverse events. However, its limited efficacy remains a concern. To address these issues, various organic polymeric nanoparticles (OPNPs) loaded with photosensitizers (PSs) that target prostate cancer have been developed. However, further optimization of the OPNP design is necessary to maximize the effectiveness of PDT and improve its clinical applicability. This Review provides an overview of the design, preparation, methodology, and oncological aspects of OPNP-based PDT for the treatment of PCa.

Effect of phospholipid head group on ultrasound-triggered drug release and cellular uptake of immunoliposomes

Liposomes are the most successful nanoparticles used to date to load and deliver chemotherapeutic agents to cancer cells. They are nano-sized vesicles made up of phospholipids, and targeting moieties can be added to their surfaces for the active targeting of specific tumors. Furthermore, Ultrasound can be used to trigger the release of the loaded drugs by disturbing their phospholipid bilayer structure. In this study, we have prepared pegylated liposomes using four types of phospholipids with similar saturated hydrocarbon tails including a phospholipid with no head group attached to the phosphate head (DPPA) and three other phospholipids with different head groups attached to their phosphate heads (DPPC, DPPE and DPPG). The prepared liposomes were conjugated to the monoclonal antibody trastuzumab (TRA) to target the human epidermal growth factor receptor 2 (HER2) overexpressed on HER2-positive cancer cells (HER2+). We have compared the response of the different formulations of liposomes when triggered with low-frequency ultrasound (LFUS) and their cellular uptake by the cancer cells. The results showed that the different formulations had similar size, polydispersity, and stability. TRA-conjugated DPPC liposomes showed the highest sensitivity to LFUS. On the other hand, incubating the cancer cells with TRA-conjugated DPPA liposomes triggered with LFUS showed the highest uptake of the loaded calcein by the HER2+ cells.

Folate-Targeted Nanoliposomal Chemophototherapy

Light-responsive liposomes have been developed for the on-demand release of drugs. However, efficient delivery of chemotherapeutic drugs to tumor for cancer theranostics remains a challenge. Herein, folic acid (FA), an established ligand for targeted drug delivery, was used to decorate light-sensitive porphyrin-phospholipid (PoP) liposomes, which were assessed for FA-targeted chemophototherapy (CPT). PoP liposomes and FA-conjugated PoP liposomes were loaded with Doxorubicin (Dox), and physical properties were characterized. In vitro, FA-PoP liposomes that were incubated with FA receptor-overexpressing human KB cancer cells showed increased uptake compared to non-targeted PoP liposomes. Dox and PoP contributed towards chemophototherapy (CPT) in vitro, and PoP and FA-PoP liposomes induced cell killing. In vivo, mice bearing subcutaneous KB tumors treated with PoP or FA-PoP liposomes loaded with Dox, followed by 665 nm laser treatment, had delayed tumor growth and improved survival. Dox delivery to tumors increased following laser irradiation for both PoP and FA-PoP liposomes. Thus, while Dox-FA-PoP liposomes were effective following systemic administration and local light irradiation in this tumor model, the FA targeting moiety did not appear essential for anti-tumor responses.

Overcoming tumor microenvironment obstacles: Current approaches for boosting nanodrug delivery

In order to achieve targeted delivery of anticancer drugs, efficacy improvement, and side effect reduction, various types of nanoparticles are employed. However, their therapeutic effects are not ideal. This phenomenon is caused by tumor microenvironment abnormalities such as abnormal blood vessels, elevated interstitial fluid pressure, and dense extracellular matrix that affect nanoparticle penetration into the tumor's interstitium. Furthermore, nanoparticle properties including size, charge, and shape affect nanoparticle transport into tumors. This review comprehensively goes over the factors hindering nanoparticle penetration into tumors and describes methods for improving nanoparticle distribution by remodeling the tumor microenvironment and optimizing nanoparticle physicochemical properties. Finally, a critical analysis of future development of nanodrug delivery in oncology is further discussed. STATEMENT OF SIGNIFICANCE: This article reviews the factors that hinder the distribution of nanoparticles in tumors, and describes existing methods and approaches for improving the tumor accumulation from the aspects of remodeling the tumor microenvironment and optimizing the properties of nanoparticles. The description of the existing methods and approaches is followed by highlighting their advantages and disadvantages and put forward possible directions for the future researches. At last, the challenges of improving tumor accumulation in nanomedicines design were also discussed. This review will be of great interest to the broad readers who are committed to delivering nanomedicine for cancer treatment.

Conjugated Polymeric Materials in Biological Imaging and Cancer Therapy

Conjugated polymers (CPs) have attracted much attention in the fields of chemistry, medicine, life science, and material science. Researchers have carried out a series of innovative researches and have made significant research progress regarding the unique photochemical and photophysical properties of CPs, expanding the application range of polymers. CPs are polymers formed by the conjugation of multiple repeating light-emitting units. Through precise control of their structure, functional molecules with different properties can be obtained. Fluorescence probes with different absorption and emission wavelengths can be obtained by changing the main chain structure. By modifying the side chain structure with water-soluble groups or selective recognition molecules, electrostatic interaction or specific binding with specific targets can be achieved; subsequently, the purpose of selective recognition can be achieved. This article reviews the research work of CPs in cell imaging, tumor diagnosis, and treatment in recent years, summarizes the latest progress in the application of CPs in imaging, tumor diagnosis, and treatment, and discusses the future development direction of CPs in cell imaging, tumor diagnosis, and treatment.

Pharmacokinetic behaviors of soft nanoparticulate formulations of chemotherapeutics

Chemotherapeutic treatment with conventional drug formulations pose numerous challenges, such as poor solubility, high cytotoxicity and serious off-target side effects, low bioavailability, and ultimately subtherapeutic tumoral concentration leading to poor therapeutic outcomes. In the field of Nanomedicine, advances in nanotechnology have been applied with great success to design and develop novel nanoparticle-based formulations for the treatment of various types of cancer. The approval of the first nanomedicine, Doxil® (liposomal doxorubicin) in 1995, paved the path for further development for various types of novel delivery platforms. Several different types of nanoparticles, especially organic (soft) nanoparticles (liposomes, polymeric micelles, and albumin-bound nanoparticles), have been developed and approved for several anticancer drugs. Nanoparticulate drug delivery platform have facilitated to overcome of these challenges and offered key advantages of improved bioavailability, higher intra-tumoral concentration of the drug, reduced toxicity, and improved efficacy. This review introduces various commonly used nanoparticulate systems in biomedical research and their pharmacokinetic (PK) attributes, then focuses on the various physicochemical and physiological factors affecting the in vivo disposition of chemotherapeutic agents encapsulated in nanoparticles in recent years. Further, it provides a review of the current landscape of soft nanoparticulate formulations for the two most widely investigated anticancer drugs, paclitaxel, and doxorubicin, that are either approved or under investigation. Formulation details, PK profiles, and therapeutic outcomes of these novel strategies have been discussed individually and in comparison, to traditional formulations. This article is categorized under: Nanotechnology Approaches to Biology > Cells at the Nanoscale Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Chemophototherapeutic Ablation of Doxorubicin-Resistant Human Ovarian Tumor Cells

Porphyrin-phospholipid (PoP) liposomes loaded with Doxorubicin (Dox) have been demonstrated to be an efficient vehicle for chemophototherapy (CPT). Multidrug resistance (MDR) of cancer cells is a problematic phenomenon in which tumor cells develop resistance to chemotherapy. Herein, we report that Dox-resistant tumor cells can be ablated using our previously described formulation termed long-circulating Dox loaded in PoP liposomes (LC-Dox-PoP), which is a PEGylated formulation containing 2 mol. % of the PoP photosensitizer. In vitro studies using free Dox and LC-Dox-PoP showed that human ovarian carcinoma A2780 cells were more susceptible to Dox compared to the corresponding Dox-resistant A2780-R cells. When CPT was applied with LC-Dox-PoP liposomes, effective killing of both nonresistant and resistant A2780 cell lines was observed. An in vivo study to assess the efficiency of LC-Dox-PoP showed effective tumor shrinkage and prolonged survival of athymic nude mice bearing subcutaneous Dox-resistant A2780-R tumor xenografts when they were irradiated with a red laser. Biodistribution analysis demonstrated enhanced tumoral drug uptake in Dox-resistant tumors with CPT, suggesting that increased drug delivery was sufficient to induce ablation of resistant tumor cells.

Liposome-based diagnostic and therapeutic applications for pancreatic cancer

Pancreatic cancer is one of the harshest and most challenging cancers to treat, often labeled as incurable. Chemotherapy continues to be the most popular treatment yet yields a very poor prognosis. The main barriers such as inefficient drug penetration and drug resistance, have led to the development of drug carrier systems. The benefits, ease of fabrication and modification of liposomes render them as ideal future drug delivery systems. This review delves into the versatility of liposomes to achieve various mechanisms of treatment for pancreatic cancer. Not only are there benefits of loading chemotherapy drugs and targeting agents onto liposomes, as well as mRNA combined therapy, but liposomes have also been exploited for immunotherapy and can be programmed to respond to photothermal therapy. Multifunctional liposomal formulations have demonstrated significant pre-clinical success. Functionalising drug-encapsulated liposomes has resulted in triggered drug release, specific targeting, and remodeling of the tumor environment. Suppressing tumor progression has been achieved, due to their ability to more efficiently and precisely deliver chemotherapy. Currently, no multifunctional surface-modified liposomes are clinically approved for pancreatic cancer thus we aim to shed light on the trials and tribulations and progress so far, with the hope for liposomal therapy in the future and improved patient outcomes. STATEMENT OF SIGNIFICANCE: Considering that conventional treatments for pancreatic cancer are highly associated with sub-optimal performance and systemic toxicity, the development of novel therapeutic strategies holds outmost relevance for pancreatic cancer management. Liposomes are being increasingly considered as promising nanocarriers for providing not only an early diagnosis but also effective, highly specific, and safer treatment, improving overall patient outcome. This manuscript is the first in the last 10 years that revises the advances in the application of liposome-based formulations in bioimaging, chemotherapy, phototherapy, immunotherapy, combination therapies, and emergent therapies for pancreatic cancer management. Prospective insights are provided regarding several advantages resulting from the use of liposome technology in precision strategies, fostering new ideas for next-generation diagnosis and targeted therapies of pancreatic cancer.

Nanosystems for gene therapy targeting brain damage caused by viral infections

Several human pathogens can cause long-lasting neurological damage. Despite the increasing clinical knowledge about these conditions, most still lack efficient therapeutic interventions. Gene therapy (GT) approaches comprise strategies to modify or adjust the expression or function of a gene, thus providing therapy for human diseases. Since recombinant nucleic acids used in GT have physicochemical limitations and can fail to reach the desired tissue, viral and non-viral vectors are applied to mediate gene delivery. Although viral vectors are associated to high levels of transfection, non-viral vectors are safer and have been further explored. Different types of nanosystems consisting of lipids, polymeric and inorganic materials are applied as non-viral vectors. In this review, we discuss potential targets for GT intervention in order to prevent neurological damage associated to infectious diseases as well as the role of nanosized non-viral vectors as agents to help the selective delivery of these gene-modifying molecules. Application of non-viral vectors for delivery of GT effectors comprise a promising alternative to treat brain inflammation induced by viral infections.

Advances in Liposome-Encapsulated Phthalocyanines for Photodynamic Therapy

This updated review aims to describe the current status in the development of liposome-based systems for the targeted delivery of phthalocyanines for photodynamic therapy (PDT). Although a number of other drug delivery systems (DDS) can be found in the literature and have been studied for phthalocyanines or similar photosensitizers (PSs), liposomes are by far the closest to clinical practice. PDT itself finds application not only in the selective destruction of tumour tissues or the treatment of microbial infections, but above all in aesthetic medicine. From the point of view of administration, some PSs can advantageously be delivered through the skin, but for phthalocyanines, systemic administration is more suitable. However, systemic administration places higher demands on advanced DDS, active tissue targeting and reduction of side effects. This review focuses on the already described liposomal DDS for phthalocyanines, but also describes examples of DDS used for structurally related PSs, which can be assumed to be applicable to phthalocyanines as well.

Increasing cancer permeability by photodynamic priming: from microenvironment to mechanotransduction signaling

The dense cancer microenvironment is a significant barrier that limits the penetration of anticancer agents, thereby restraining the efficacy of molecular and nanoscale cancer therapeutics. Developing new strategies to enhance the permeability of cancer tissues is of major interest to overcome treatment resistance. Nonetheless, early strategies based on small molecule inhibitors or matrix-degrading enzymes have led to disappointing clinical outcomes by causing increased chemotherapy toxicity and promoting disease progression. In recent years, photodynamic therapy (PDT) has emerged as a novel approach to increase the permeability of cancer tissues. By producing excessive amounts of reactive oxygen species selectively in the cancer microenvironment, PDT increases the accumulation, penetration depth, and efficacy of chemotherapeutics. Importantly, the increased cancer permeability has not been associated to increased metastasis formation. In this review, we provide novel insights into the mechanisms by which this effect, called photodynamic priming, can increase cancer permeability without promoting cell migration and dissemination. This review demonstrates that PDT oxidizes and degrades extracellular matrix proteins, reduces the capacity of cancer cells to adhere to the altered matrix, and interferes with mechanotransduction pathways that promote cancer cell migration and differentiation. Significant knowledge gaps are identified regarding the involvement of critical signaling pathways, and to which extent these events are influenced by the complicated PDT dosimetry. Addressing these knowledge gaps will be vital to further develop PDT as an adjuvant approach to improve cancer permeability, demonstrate the safety and efficacy of this priming approach, and render more cancer patients eligible to receive life-extending treatments.

Carbon nanomaterials for drug delivery and tissue engineering

Carbon nanomaterials are some of the state-of-the-art materials used in drug-delivery and tissue-engineering research. Compared with traditional materials, carbon nanomaterials have the advantages of large specific surface areas and unique properties and are more suitable for use in drug delivery and tissue engineering after modification. Their characteristics, such as high drug loading and tissue loading, good biocompatibility, good targeting and long duration of action, indicate their great development potential for biomedical applications. In this paper, the synthesis and application of carbon dots (CDs), carbon nanotubes (CNTs) and graphene in drug delivery and tissue engineering are reviewed in detail. In this review, we discuss the current research focus and existing problems of carbon nanomaterials in order to provide a reference for the safe and effective application of carbon nanomaterials in drug delivery and tissue engineering.

An update on dual targeting strategy for cancer treatment

The key issue in the treatment of solid tumors is the lack of efficient strategies for the targeted delivery and accumulation of therapeutic cargoes in the tumor microenvironment (TME). Targeting approaches are designed for more efficient delivery of therapeutic agents to cancer cells while minimizing drug toxicity to normal cells and off-targeting effects, while maximizing the eradication of cancer cells. The highly complicated interrelationship between the physicochemical properties of nanoparticles, and the physiological and pathological barriers that are required to cross, dictates the need for the success of targeting strategies. Dual targeting is an approach that uses both purely biological strategies and physicochemical responsive smart delivery strategies to increase the accumulation of nanoparticles within the TME and improve targeting efficiency towards cancer cells. In both approaches, either one single ligand is used for targeting a single receptor on different cells, or two different ligands for targeting two different receptors on the same or different cells. Smart delivery strategies are able to respond to triggers that are typical of specific disease sites, such as pH, certain specific enzymes, or redox conditions. These strategies are expected to lead to more precise targeting and better accumulation of nano-therapeutics. This review describes the classification and principles of dual targeting approaches and critically reviews the efficiency of dual targeting strategies, and the rationale behind the choice of ligands. We focus on new approaches for smart drug delivery in which synthetic and/or biological moieties are attached to nanoparticles by TME-specific responsive linkers and advanced camouflaged nanoparticles.

Folate Decorated Multifunctional Biodegradable Nanoparticles for Gastric Carcinoma Active Targeting Theranostics

Introduction

Gastric cancer remains a major clinical issue and little progress has been made in the treatment of gastric cancer patients during recent decades. Nanoparticles provide a versatile platform for the diagnosis and treatment of gastric cancer.

Methods

We prepared 7-ethyl-10-hydroxycamptothecin (SN-38) ¹²⁵I-radiolabelled biodegradable nanoparticles with folate surface modification (¹²⁵I-SN-38-FA-NPs) as a novel nanoplatform for targeted gastric carcinoma theranostics. We characterized this system in terms of particle size, morphology, radiostability, and release properties and examined the in vitro cytotoxicity and cellular uptake properties of ¹²⁵I-SN-38-FA-NPs in MNK 7 and NCI-N7 cells. The pharmacokinetics and biodistribution of ¹²⁵I-SN-38-FA-NPs were imaged by single photon emission computer tomography (SPECT). An MNK7 tumor-bearing model were established and the in vivo antitumor activity of ¹²⁵I-SN-38-FA-NPs was evaluated.

Results

SN-38 was readily radiolabeled with ¹²⁵I and exhibited high radiostability. Poly-lactic-co-glycolic acid (PLGA) nanoparticles (NPs) were formed by solvent exchange, and displayed spherical morphology of 100 nm in diameter as characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). A 2.5-fold greater uptake of ¹²⁵I-radiolabelled SN-38-loaded folate-decorated PLGA nanoparticles (¹²⁵I-SN-38-FA-NPs) than ¹²⁵I-radiolabelled SN-38-loaded PLGA nanoparticles (¹²⁵I-SN-38-NPs) were record in MKN7 tumor cells. NPs and folate-decorated PLGA nanoparticles (FA-NPs) also had good biocompatibility in methyl thiazolyl tetrazolium (MTT) assays. Pharmacokinetic, biodistribution and SPECT imaging studies showed that ¹²⁵I-SN-38-FA-NPs had prolonged circulation, were distributed in the reticuloendothelial system, and had high uptake in tumors with a higher tumor accumulation of ¹²⁵I-SN-38-FA-NPs than ¹²⁵I-SN-38-NPs recorded at 24 h postinjection. In vivo SN-38-FA-NPs significantly inhibited tumor growth without causing obvious side effects.

Conclusion

Folate receptor alpha (FOLR1) targeted drug-loaded nanoparticles enable SPECT imaging and chemotherapy, and provide a novel nanoplatform for gastric carcinoma active targeting theranostics.

One-Pot, One-Step Synthesis of Drug-Loaded Magnetic Multimicelle Aggregates

Lipid-based formulations provide a nanotechnology platform that is widely used in a variety of biomedical applications because it has several advantageous properties including biocompatibility, reduced toxicity, relative ease of surface modifications, and the possibility for efficient loading of drugs, biologics, and nanoparticles. A combination of lipid-based formulations with magnetic nanoparticles such as iron oxide was shown to be highly advantageous in a growing number of applications including magnet-mediated drug delivery and image-guided therapy. Currently, lipid-based formulations are prepared by multistep protocols. Simplification of the current multistep procedures can lead to a number of important technological advantages including significantly decreased processing time, higher reaction yield, better product reproducibility, and improved quality. Here, we introduce a one-pot, single-step synthesis of drug-loaded magnetic multimicelle aggregates (MaMAs), which is based on controlled flow infusion of an iron oxide nanoparticle/lipid mixture into an aqueous drug solution under ultrasonication. Furthermore, we prepared molecular-targeted MaMAs by directional antibody conjugation through an Fc moiety using Cu-free click chemistry. Fluorescence imaging and quantification confirmed that antibody-conjugated MaMAs showed high cell-specific targeting that was enhanced by magnetic delivery.

Single-treatment tumor ablation with photodynamic liposomal irinotecan sucrosulfate

Irinotecan (IRI) loaded actively into PEGylated liposomes via a sucrosulfate gradient has been approved recently to treat advanced pancreatic cancer. In this study, a similar liposomal composition was developed that includes a low mole fraction (1 mol.%) of porphyrin-phospholipid (PoP), a photosensitizer that stably incorporates into liposomes, to confer light-triggered IRI release. IRI-loaded PoP liposomes containing ammonium sucrosulfate (ASOS) as a complexing agent were more stable in serum compared to liposomes employing the more conventional ammonium sulfate. Without irradiation, PoP IRI liposomes released less than 5% IRI during 8 h of incubation in bovine serum at 37 °C, but released over 90% of the drug within minutes of exposure to red light (665 nm) irradiation. A single treatment with IRI-PoP liposomes and light exposure (15 mg/kg IRI with 250 J/cm2) resulted in tumor eradication in mice bearing either MIA PaCa-2 tumors or low-passage patient-derived tumor xenografts that recapitulate characteristics of the clinical disease. Analogous monotherapies of IRI or photodynamic therapy were ineffective in controlling tumor growth. Enhanced drug uptake could be visualized within laser-treated tumors by direct in situ imaging of irinotecan. Biodistribution analysis of IRI, its active metabolite (SN-38), and major metabolite (SN-38 G) showed that laser treatment significantly increased tumor accumulation of all IRI-derived molecular species. A pharmacokinetic model that hypothesized tumor vasculature permeabilization as the primary reason underlying the increased drug deposition accounted for the enhanced drug influx into tumors.

Nanocarrier cancer therapeutics with functional stimuli-responsive mechanisms

Presently, nanocarriers (NCs) have gained huge attention for their structural ability, good biocompatibility, and biodegradability. The development of effective NCs with stimuli-responsive properties has acquired a huge interest among scientists. When developing drug delivery NCs, the fundamental goal is to tackle the delivery-related problems associated with standard chemotherapy and to carry medicines to the intended sites of action while avoiding undesirable side effects. These nanocarriers were able of delivering drugs to tumors through regulating their pH, temperature, enzyme responsiveness. With the use of nanocarriers, chemotherapeutic drugs could be supplied to tumors more accurately that can equally encapsulate and deliver them. Material carriers for chemotherapeutic medicines are discussed in this review keeping in viewpoint of the structural properties and targeting methods that make these carriers more therapeutically effective, in addition to metabolic pathways triggered by drug-loaded NCs. Largely, the development of NCs countering to endogenous and exogenous stimuli in tumor regions and understanding of mechanisms would encourage the progress for tumor therapy and precision diagnosis in future.

Advances in Photodynamic Therapy Based on Nanotechnology and Its Application in Skin Cancer

Comprehensive cancer treatments have been widely studied. Traditional treatment methods (e.g., radiotherapy, chemotherapy), despite ablating tumors, inevitably damage normal cells and cause serious complications. Photodynamic therapy (PDT), with its low rate of trauma, accurate targeting, synergism, repeatability, has displayed great advantages in the treatment of tumors. In recent years, nanotech-based PDT has provided a new modality for cancer treatment. Direct modification of PSs by nanotechnology or the delivery of PSs by nanocarriers can improve their targeting, specificity, and PDT efficacy for tumors. In this review, we strive to provide the reader with a comprehensive overview, on various aspects of the types, characteristics, and research progress of photosensitizers and nanomaterials used in PDT. And the application progress and relative limitations of nanotech-PDT in non-melanoma skin cancer and melanoma are also summarized.

Synthetic cells in biomedical applications

Synthetic cells are engineered vesicles that can mimic one or more salient features of life. These features include directed localization, sense-and-respond behavior, gene expression, metabolism, and high stability. In nanomedicine, many of these features are desirable capabilities of drug delivery vehicles but are difficult to engineer. In this focus article, we discuss where synthetic cells offer unique advantages over nanoparticle and living cell therapies. We review progress in the engineering of the above life-like behaviors and how they are deployed in nanomedicine. Finally, we assess key challenges synthetic cells face before being deployed as drugs and suggest ways to overcome these challenges. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Biology-Inspired Nanomaterials > Lipid-Based Structures.

Liposomes, new carriers for delivery of genes and anticancer drugs: a systematic review

Today, nanoscience has grown and developed in various fields of medicine and treatment, including cancer treatment. Currently, the existing treatments, including chemotherapy and radiotherapy, cause side effects that are unpleasant to the patient. Due to the fact that anticancer drugs cause severe and widespread side effects, liposomes are considered as new drug carriers to minimize the untimely destruction of the drug when it is delivered to the target tissue and to prevent the side effects of toxic drugs. This systematic review study examined the importance of using liposomes as new drug carriers for the delivery of genes and anticancer drugs. The articles published in English in the databases of Google scholar, WoS, PubMed, Embase, Scopus and science direct were reviewed. According to the results of this study, a new targeted nanosystem has been used for loading and delivering anticancer drugs, genes and controlled drug release which has a significant therapeutic effect compared to the same amount of free drug. In general, liposomal systems have been considered because of their capability in preserving the effect of the drug along with reducing the side effects and toxicity of the drug, especially in the case of anticancer drugs. Accumulation of the drug in a target tissue which results in a reduction of the drug entry into other tissues is the main reason for reducing the side effects of these drugs.

Combined Fluorescence and Optoacoustic Imaging for Monitoring Treatments against CT26 Tumors with Photoactivatable Liposomes

The newly developed multimodal imaging system combining raster-scan optoacoustic (OA) microscopy and fluorescence (FL) wide-field imaging was used for characterizing the tumor vascular structure with 38/50 μm axial/transverse resolution and assessment of photosensitizer fluorescence kinetics during treatment with novel theranostic agents. A multifunctional photoactivatable multi-inhibitor liposomal (PMILs) nano platform was engineered here, containing a clinically approved photosensitizer, Benzoporphyrin derivative (BPD) in the bilayer, and topoisomerase I inhibitor, Irinotecan (IRI) in its inner core, for a synergetic therapeutic impact. The optimized PMIL was anionic, with the hydrodynamic diameter of 131.6 ± 2.1 nm and polydispersity index (PDI) of 0.05 ± 0.01, and the zeta potential between -14.9 ± 1.04 to -16.9 ± 0.92 mV. In the in vivo studies on BALB/c mice with CT26 tumors were performed to evaluate PMILs' therapeutic efficacy. PMILs demonstrated the best inhibitory effect of 97% on tumor growth compared to the treatment with BPD-PC containing liposomes (PALs), 81%, or IRI containing liposomes (L-[IRI]) alone, 50%. This confirms the release of IRI within the tumor cells upon PMILs triggering by NIR light, which is additionally illustrated by FL monitoring demonstrating enhancement of drug accumulation in tumor initiated by PDT in 24 h after the treatment. OA monitoring revealed the largest alterations of the tumor vascular structure in the PMILs treated mice as compared to BPD-PC or IRI treated mice. The results were further corroborated with histological data that also showed a 5-fold higher percentage of hemorrhages in PMIL treated mice compared to the control groups. Overall, these results suggest that multifunctional PMILs simultaneously delivering PDT and chemotherapy agents along with OA and FL multi-modal imaging offers an efficient and personalized image-guided platform to improve cancer treatment outcomes.

Two Laser Treatments Can Improve Tumor Ablation Efficiency of Chemophototherapy

Chemophototherapy is an emerging tumor ablation modality that can improve local delivery of chemotherapeutic agents. Long circulating doxorubicin (Dox) in porphyrin-phospholipid (PoP) liposomes (LC-Dox-PoP) has previously been developed as an effective chemophototherapy agent. In the present study, we observed that in mice, LC-Dox-PoP showed enhanced accumulation in human pancreatic tumor xenografts even with suboptimal light doses, as assessed by fluorometric analysis of tissue homogenates and microscopic imaging of Dox and PoP in tumor slices. A second laser treatment, at a time point in which tumors had greater drug accumulation as a result of the first laser treatment, induced potent tumor ablation. Efficacy studies were carried out in two human pancreatic cancer subcutaneous mouse tumor models; MIA PaCa-2 or low-passage patient derived pancreatic cancer xenografts. A single treatment of 3 mg/kg LC-Dox-PoP and an initial 150 J/cm² laser treatment 1 h after drug administration, followed by second laser treatment of 50 J/cm² 8 h after drug administration, was more effective than a single laser treatment of 200 J/cm² at either of those time points. Thus, this study presents proof-of-principle and rationale for using two discrete laser treatments to enhance the efficacy of chemophototherapy.

Precision biomaterials in cancer theranostics and modelling

Despite significant achievements in the understanding and treatment of cancer, it remains a major burden. Traditional therapeutic approaches based on the 'one-size-fits-all' paradigm are becoming obsolete, as demonstrated by the increasing number of patients failing to respond to treatments. In contrast, more precise approaches based on individualized genetic profiling of tumors have already demonstrated their potential. However, even more personalized treatments display shortcomings mainly associated with systemic delivery, such as low local drug efficacy or specificity. A large amount of effort is currently being invested in developing precision medicine-based strategies for improving the efficiency of cancer theranostics and modelling, which are envisioned to be more accurate, standardized, localized, and less expensive. To this end, interdisciplinary research fields, such as biomedicine, material sciences, pharmacology, chemistry, tissue engineering, and nanotechnology, must converge for boosting the precision cancer ecosystem. In this regard, precision biomaterials have emerged as a promising strategy to detect, model, and treat cancer more efficiently. These are defined as those biomaterials precisely engineered with specific theranostic functions and bioactive components, with the possibility to be tailored to the cancer patient needs, thus having a vast potential in the increasing demand for more efficient treatments. In this review, we discuss the latest advances in the field of precision biomaterials in cancer research, which are expected to revolutionize disease management, focusing on their uses for cancer modelling, detection, and therapeutic applications. We finally comment on the needed requirements to accelerate their application in the clinic to improve cancer patient prognosis.

Nanomedicine in Pancreatic Cancer: Current Status and Future Opportunities for Overcoming Therapy Resistance

Simple Summary

Despite access to a vast arsenal of anticancer agents, many fail to realise their full therapeutic potential in clinical practice. One key determinant of this is the evolution of multifaceted resistance mechanisms within the tumour that may either pre-exist or develop during the course of therapy. This is particularly evident in pancreatic cancer, where limited responses to treatment underlie dismal survival rates, highlighting the urgent need for new therapeutic approaches. Here, we discuss the major features of pancreatic tumours that contribute to therapy resistance, and how they may be alleviated through exploitation of the mounting and exciting promise of nanomedicines; a unique collection of nanoscale platforms with tunable and multifunctional capabilities that have already elicited a widespread impact on cancer management.

Abstract

The development of drug resistance remains one of the greatest clinical oncology challenges that can radically dampen the prospect of achieving complete and durable tumour control. Efforts to mitigate drug resistance are therefore of utmost importance, and nanotechnology is rapidly emerging for its potential to overcome such issues. Studies have showcased the ability of nanomedicines to bypass drug efflux pumps, counteract immune suppression, serve as radioenhancers, correct metabolic disturbances and elicit numerous other effects that collectively alleviate various mechanisms of tumour resistance. Much of this progress can be attributed to the remarkable benefits that nanoparticles offer as drug delivery vehicles, such as improvements in pharmacokinetics, protection against degradation and spatiotemporally controlled release kinetics. These attributes provide scope for precision targeting of drugs to tumours that can enhance sensitivity to treatment and have formed the basis for the successful clinical translation of multiple nanoformulations to date. In this review, we focus on the longstanding reputation of pancreatic cancer as one of the most difficult-to-treat malignancies where resistance plays a dominant role in therapy failure. We outline the mechanisms that contribute to the treatment-refractory nature of these tumours, and how they may be effectively addressed by harnessing the unique capabilities of nanomedicines. Moreover, we include a brief perspective on the likely future direction of nanotechnology in pancreatic cancer, discussing how efforts to develop multidrug formulations will guide the field further towards a therapeutic solution for these highly intractable tumours.

NIR irradiation-controlled drug release utilizing injectable hydrogels containing gold-labeled liposomes for the treatment of melanoma cancer

Drug-based chemotherapy is associated with serious side effects. We developed a chemotherapeutic system comprising a chitosan hydrogel (CH-HG) containing gold cluster-labeled liposomal doxorubicin (DOX) (CH-HG-GL_DOX) as an injectable drug depot system. CH-HG-GL_DOX can be directly injected into tumor tissue without a surgical procedure, allowing this system to act as a reservoir for liposomal DOX. CH-HG-GL_DOX enhanced the retention time of DOX in tumor tissue and controlled its release in response to near-infrared (NIR) irradiation, resulting in significant inhibition of tumor growth and reduced DOX-related toxicity. The combined effect of CH-HG-GL_DOX and poly (D,L-lactide-co-glycolic acid) nanoparticle-based vaccines increased cytotoxic CD8+ T cell immunity, leading to enhanced synergistic therapeutic efficacy. CH-HG-GL_DOX provides an advanced therapeutic approach for local drug delivery and controlled release of DOX, resulting in reduced toxicity. Here, we suggest a combination strategy for chemo- and immunotherapies, as well as in nanomedicine applications. STATEMENT OF SIGNIFICANCE: We developed an injectable hydrogel containing gold cluster-labeled liposomes for sustained drug release at the tumor site. Moreover, we demonstrated the combined therapeutic efficacy of a hydrogel system and a nanoparticle-based immunotherapeutic vaccine for melanoma cancer. Thus, we show a potential combination approach for chemo- and immunotherapies for cancer treatment.

Progress in Nanocarriers Codelivery System to Enhance the Anticancer Effect of Photodynamic Therapy

Photodynamic therapy (PDT) is a promising anticancer noninvasive method and has great potential for clinical applications. Unfortunately, PDT still has many limitations, such as metastatic tumor at unknown sites, inadequate light delivery and a lack of sufficient oxygen. Recent studies have demonstrated that photodynamic therapy in combination with other therapies can enhance anticancer effects. The development of new nanomaterials provides a platform for the codelivery of two or more therapeutic drugs, which is a promising cancer treatment method. The use of multifunctional nanocarriers for the codelivery of two or more drugs can improve physical and chemical properties, increase tumor site aggregation, and enhance the antitumor effect through synergistic actions, which is worthy of further study. This review focuses on the latest research progress on the synergistic enhancement of PDT by simultaneous multidrug administration using codelivery nanocarriers. We introduce the design of codelivery nanocarriers and discuss the mechanism of PDT combined with other antitumor methods. The combination of PDT and chemotherapy, gene therapy, immunotherapy, photothermal therapy, hyperthermia, radiotherapy, sonodynamic therapy and even multidrug therapy are discussed to provide a comprehensive understanding.

Photo-triggerable liposomes based on lipid-porphyrin conjugate and cholesterol combination: Formulation and mechanistic study on monolayers and bilayers

Lipid-porphyrin conjugates are considered nowadays as promising building blocks for the conception of drug delivery systems with multifunctional properties such as photothermal therapy (PTT), photodynamic therapy (PDT), phototriggerable release, photoacoustic and fluorescence imaging. For this aim, we have recently synthesized a new lipid-porphyrin conjugate named PhLSM. This was obtained by coupling pheophorbide-a (Pheo-a), a photosensitizer derived from chlorophyll-a, to egg lyso-sphingomyelin. The pure PhLSMs were able to self-assemble into vesicle-like structures that were however not stable and formed aggregates with undefined structures due to the mismatch between the length of the alkyl chain in sn-1 position and the adjacent porphyrin. Herein, stable PhLSMs lipid bilayers were achieved by mixing PhLSMs with cholesterol which exhibits a complementary packing parameter. The interfacial behavior as well as the fine structures of their equimolar mixture was studied at the air/buffer interface by the mean of Langmuir balance and x-ray reflectomerty (XRR) respectively. Our XRR analysis unraveled the monolayer thickening and the increase in the lateral ordering of PhLSM molecules. Interestingly, we could prepare stable vesicles with this mixture that encapsulate hydrophilic fluorescent probe. The light-triggered release kinetics and the photothermal conversion were studied. Moreover, the obtained vesicles were photo-triggerable and allowed the release of an encapsulated cargo in an ON-OFF fashion.

Doxorubicin-Sensitized Luminescence of NIR-Emitting Ytterbium Liposomes: Towards Direct Monitoring of Drug Release

Drug-loaded liposomes are typical examples of nanomedicines. We show here that doxorubicin, the anti-cancer agent in the liposomal drug Doxil, can sensitize Ytterbium (Yb³⁺ ) and generate its near-infrared (NIR) emission. When doxorubicin and amphiphilic Yb³⁺ chelates are incorporated into liposomes, the sensitized emission of Yb³⁺ is dependent on the integrity of the particles, which can be used to monitor drug release. We also established the first demonstration that the NIR Yb³⁺ emission signal is observable in living mice following intratumoral injection of the Yb³⁺ -doxorubicin-liposomes, using a commercial macroscopic setup equipped with a NIR camera.

Intratumoral Photosensitizer Delivery and Photodynamic Therapy

Photodynamic therapy (PDT) is a two-step procedure that involves the administration of special drugs, commonly called photosensitizers, followed by the application of certain wavelengths of light. The light activates these photosensitizers to produce reactive molecular species that induce cell death in tissues. There are numerous factors to consider when selecting the appropriate photosensitizer administration route, such as which part of the body is being targeted, the pharmacokinetics of photosensitizers, and the formulation of photosensitizers. While intravenous, topical, and oral administration of photosensitizers are widely used in preclinical and clinical applications of PDT, other administration routes, such as intraperitoneal, intra-arterial, and intratumoral injections, are gaining traction for their potential in treating advanced diseases and reducing off-target toxicities. With recent advances in targeted nanotechnology, biomaterials, and light delivery systems, the exciting possibilities of targeted photosensitizer delivery can be fully realized for preclinical and clinical applications. Further, in light of the growing burden of cancer mortality in low and middle-income countries and development of low-cost light sources and photosensitizers, PDT could be used to treat cancer patients in low-income settings. This short article introduces aspects of interfaces of intratumoral photosensitizer injections and nano-biomaterials for PDT applications in both high-income and low-income settings but does not present a comprehensive review due to space limitations.

An insight into the risk factors of brain tumors and their therapeutic interventions

Brain tumors are an abnormal growth of cells in the brain, also known as multifactorial groups of neoplasm. Incidence rates of brain tumors increase rapidly, and it has become a leading cause of tumor related deaths globally. Several factors have potential risks for intracranial neoplasm. To date, the International Agency for Research on Cancer has classified the ionizing radiation and the N-nitroso compounds as established carcinogens and probable carcinogens respectively. Diagnosis of brain tumors is based on histopathology and suitable imaging techniques. Labeled amino acids and fluorodeoxyglucose with or without contrast-enhanced MRI are used for the evaluation of tumor traces. T2-weighted MRI is an advanced diagnostic implementation, used for the detection of low-grade gliomas. Treatment decisions are based on tumor size, location, type, patient's age and health status. Conventional therapeutic approaches for tumor treatment are surgery, radiotherapy and chemotherapy. While the novel strategies may include targeted therapy, electric field treatments and vaccine therapy. Inhibition of cyclin-dependent kinase inhibitors is an attractive tumor mitigation strategy for advanced-stage cancers; in the future, it may prove to be a useful targeted therapy. The blood-brain barrier poses a major hurdle in the transport of therapeutics towards brain tissues. Moreover, nanomedicine has gained a vital role in cancer therapy. Nano drug delivery system such as liposomal drug delivery has been widely used in the cancer treatment. Liposome encapsulated drugs have improved therapeutic efficacy than free drugs. Numerous treatment therapies for brain tumors are in advanced clinical research.

DNA Based and Stimuli-Responsive Smart Nanocarrier for Diagnosis and Treatment of Cancer: Applications and Challenges

The rapid development of multidrug co-delivery and nano-medicines has made spontaneous progress in tumor treatment and diagnosis. DNA is a unique biological molecule that can be tailored and molded into various nanostructures. The addition of ligands or stimuli-responsive elements enables DNA nanostructures to mediate highly targeted drug delivery to the cancer cells. Smart DNA nanostructures, owing to their various shapes, sizes, geometry, sequences, and characteristics, have various modes of cellular internalization and final disposition. On the other hand, functionalized DNA nanocarriers have specific receptor-mediated uptake, and most of these ligand anchored nanostructures able to escape lysosomal degradation. DNA-based and stimuli responsive nano-carrier systems are the latest advancement in cancer targeting. The data exploration from various studies demonstrated that the DNA nanostructure and stimuli responsive drug delivery systems are perfect tools to overcome the problems existing in the cancer treatment including toxicity and compromised drug efficacy. In this light, the review summarized the insights about various types of DNA nanostructures and stimuli responsive nanocarrier systems applications for diagnosis and treatment of cancer.

Nanoparticles as a Tool in Neuro-Oncology Theranostics

The rapid growth of nanotechnology and the development of novel nanomaterials with unique physicochemical characteristics provides potential for the utility of nanomaterials in theranostics, including neuroimaging, for identifying neurodegenerative changes or central nervous system malignancy. Here we present a systematic and thorough review of the current evidence pertaining to the imaging characteristics of various nanomaterials, their associated toxicity profiles, and mechanisms for enhancing tropism in an effort to demonstrate the utility of nanoparticles as an imaging tool in neuro-oncology. Particular attention is given to carbon-based and metal oxide nanoparticles and their theranostic utility in MRI, CT, photoacoustic imaging, PET imaging, fluorescent and NIR fluorescent imaging, and SPECT imaging.

Optimized Photoactivatable Lipid Nanoparticles Enable Red Light Triggered Drug Release

Encapsulation of small molecule drugs in long-circulating lipid nanoparticles (LNPs) can reduce toxic side effects and enhance accumulation at tumor sites. A fundamental problem, however, is the slow release of encapsulated drugs from these liposomal systems at the disease site resulting in limited therapeutic benefit. Methods to trigger release at specific sites are highly warranted. Here, it is demonstrated that incorporation of ultraviolet (UV-A) or red-light photoswitchable-phosphatidylcholine analogs (AzoPC and redAzoPC) in conventional LNPs generates photoactivatable LNPs (paLNPs) having comparable structural integrity, drug loading capacity, and size distribution to the parent DSPC-cholesterol liposomes. It is shown that 65-70% drug release (doxorubicin) can be induced from these systems by irradiation with pulsed light based on trans-to-cis azobenzene isomerization. In vitro it is confirmed that paLNPs are non-toxic in the dark but convey cytotoxicity upon irradiation in a human cancer cell line. In vivo studies in zebrafish embryos demonstrate prolonged blood circulation and extravasation of paLNPs comparable to clinically approved formulations, with enhanced drug release following irradiation with pulsed light. Conclusively, paLNPs closely mimic the properties of clinically approved LNPs with the added benefit of light-induced drug release making them promising candidates for clinical development.

Biomimetic Liposomal Nanoplatinum for Targeted Cancer Chemophototherapy

Photodynamic therapy (PDT) of cancer is limited by tumor hypoxia. Platinum nanoparticles (nano-Pt) as a catalase-like nanoenzyme can enhance PDT through catalytic oxygen supply. However, the cytotoxic activity of nano-Pt is not comprehensively considered in the existing methods to exert their multifunctional antitumor effects. Here, nano-Pt are loaded into liposomes via reverse phase evaporation. The clinical photosensitizer verteporfin (VP) is loaded in the lipid bilayer to confer PDT activity. Murine macrophage cell membranes are hybridized into the liposomal membrane to confer biomimetic and targeting features. The resulting liposomal system, termed "nano-Pt/VP@MLipo," is investigated for chemophototherapy in vitro and in vivo in mouse tumor models. At the tumor site, oxygen produced by nano-Pt catalyzation improves the VP-mediated PDT, which in turn triggers the release of nano-Pt via membrane permeabilization. The ultrasmall 3-5 nm nano-Pt enables better penetration in tumors, which is also facilitated by the generated oxygen gas, for enhanced chemotherapy. Chemophototherapy with a single injection of nano-Pt/VP@MLipo and light irradiation inhibits the growth of aggressive 4T1 tumors and their lung metastasis, and prolongs animal survival without overt toxicity.

Formulation and Applications of Lipid-Based Nanovehicles: Spotlight on Self-emulsifying Systems

The drug delivery investigation field is continuously widened and adapted to overcome many factors such as poor drug solubility, absorption, rapid metabolism, the variability of drug plasma levels, cellular efflux and many others. Due to resemblance to body constituents and their biocompatibility, lipids offer a promising scheme for poorly water-soluble and lipophilic drugs. Various nanoparticles including vesicular systems, lipid particulate systems, and emulsion systems provide some unique benefits as pharmaceutical carriers in drug and biomolecules delivery systems. Nowadays synthesis is directed toward simple, costless techniques, therefore, self-emulsifying systems have gained superiority over the other carriers. Self nano-emulsifying systems composed of oil, surfactant, and co-surfactant emulsified upon contact with an aqueous medium, has been widely exploited. This review attempts to provide a comprehensive interpretation of different types of lipid-based carriers emphasizing on the self-nanoemulsifying system, why it is gaining interest, formulation, composition, and applications.

A moisture balanced antibacterial dressing loaded with lysozyme possesses antibacterial activity and promotes wound healing

Wound moisture management is very important in wound healing. Previous wound management has included dry healing and moist healing, and the theory of wound moisture balance is currently generally accepted. However, current studies have not reported which humidity is suitable for wound healing and how to appropriately use antibacterial compounds when the humidity is suitable. Our study explored the moisture balance of polyurethane foam dressings through a moisture balance test and constructed a safe and effective moisture balanced antibacterial dressing by loading lysozyme onto a polyurethane foam dressing. Wound healing experiments showed that the wound healing speed was the fastest when the humidity was 25%. In vivo and in vitro antibacterial experiments showed the superior antibacterial performance of the dressing after lysozyme loading. We loaded lysozyme on moisture balanced polyurethane dressings by means of dopamine adsorption, and the modified dressings were named PU/DA-LYS (polyurethane/dopamine-lysozyme). Experiments on wound healing in infected mice indicated that PU/DA-LYS helps fight infection while promoting wound healing. Cytotoxicity experiments and in vivo biological safety experiments indicated that PU/DA-LYS was safe for use. Our study found that the lysozyme loaded polyurethane dressing can provide appropriate wound moisture and prevent bacterial infection, which is a future developmental direction for wound dressings.

Triggered Drug Release From Liposomes: Exploiting the Outer and Inner Tumor Environment

Since more than 40 years liposomes have being extensively studied for their potential as carriers of anticancer drugs. The basic principle behind their use for cancer treatment consists on the idea that they can take advantage of the leaky vasculature and poor lymphatic drainage present at the tumor tissue, passively accumulating in this region. Aiming to further improve their efficacy, different strategies have been employed such as PEGlation, which enables longer circulation times, or the attachment of ligands to liposomal surface for active targeting of cancer cells. A great challenge for drug delivery to cancer treatment now, is the possibility to trigger release from nanosystems at the tumor site, providing efficacious levels of drug in the tumor. Different strategies have been proposed to exploit the outer and inner tumor environment for triggering drug release from liposomes and are the focus of this review.

Synergistic Cancer Photochemotherapy via Layered Double Hydroxide-Based Trimodal Nanomedicine at Very Low Therapeutic Doses

The success of cancer therapy is always accompanied by severe side effects due to the high amount of toxic antitumor drugs that off-target normal organs/tissues. Herein, we report the development of a trifunctional layered double hydroxide (LDH) nanosystem for combined photochemotherapy of skin cancer at very low therapeutic doses. This nanosystem (ICG/Cu-LDH@BSA-DOX) is composed of acid-responsive bovine serum albumin-doxorubicin prodrug (BSA-DOX) and indocyanine green (ICG)-intercalated Cu-doped LDH nanoparticle. ICG/Cu-LDH@BSA-DOX is able to release DOX in an acid-triggered manner, efficiently and simultaneously generates heating and reactive oxygen species (ROS) upon 808 nm laser irradiation, and synergistically induces apoptosis of skin cancer cells. In vivo therapeutic evaluations demonstrate that ICG/Cu-LDH@BSA-DOX nearly eradicated the tumor tissues upon one-course treatment using very low doses of therapeutic agents (0.175 mg/kg DOX, 0.5 mg/kg Cu, and 0.25 mg/kg ICG) upon very mild 808 nm laser irradiation (0.3 W/cm² for 2 min). This work thus provides a novel strategy to design anticancer nanomedicine for efficient combination cancer treatment with minimal side effects in clinical applications.

Recent Advancements in Stimuli Responsive Drug Delivery Platforms for Active and Passive Cancer Targeting

The tumor-specific targeting of chemotherapeutic agents for specific necrosis of cancer cells without affecting the normal cells poses a great challenge for researchers and scientists. Though extensive research has been carried out to investigate chemotherapy-based targeted drug delivery, the identification of the most promising strategy capable of bypassing non-specific cytotoxicity is still a major concern. Recent advancements in the arena of onco-targeted therapies have enabled safe and effective tumor-specific localization through stimuli-responsive drug delivery systems. Owing to their promising characteristic features, stimuli-responsive drug delivery platforms have revolutionized the chemotherapy-based treatments with added benefits of enhanced bioavailability and selective cytotoxicity of cancer cells compared to the conventional modalities. The insensitivity of stimuli-responsive drug delivery platforms when exposed to normal cells prevents the release of cytotoxic drugs into the normal cells and therefore alleviates the off-target events associated with chemotherapy. Contrastingly, they showed amplified sensitivity and triggered release of chemotherapeutic payload when internalized into the tumor microenvironment causing maximum cytotoxic responses and the induction of cancer cell necrosis. This review focuses on the physical stimuli-responsive drug delivery systems and chemical stimuli-responsive drug delivery systems for triggered cancer chemotherapy through active and/or passive targeting. Moreover, the review also provided a brief insight into the molecular dynamic simulations associated with stimuli-based tumor targeting.

Photosensitizer Nanoparticles Boost Photodynamic Therapy for Pancreatic Cancer Treatment

Patients with pancreatic cancer (PCa) have a poor prognosis apart from the few suitable for surgery. Photodynamic therapy (PDT) is a minimally invasive treatment modality whose efficacy and safety in treating unresectable localized PCa have been corroborated in clinic. Yet, it suffers from certain limitations during clinical exploitation, including insufficient photosensitizers (PSs) delivery, tumor-oxygenation dependency, and treatment escape of aggressive tumors. To overcome these obstacles, an increasing number of researchers are currently on a quest to develop photosensitizer nanoparticles (NPs) by the use of a variety of nanocarrier systems to improve cellular uptake and biodistribution of photosensitizers. Encapsulation of PSs with NPs endows them significantly higher accumulation within PCa tumors due to the increased solubility and stability in blood circulation. A number of approaches have been explored to produce NPs co-delivering multi-agents affording PDT-based synergistic therapies for improved response rates and durability of response after treatment. This review provides an overview of available data regarding the design, methodology, and oncological outcome of the innovative NPs-based PDT of PCa.